The present disclosure relates to an image processing apparatus, an image processing method, and a computer readable recording medium.
In recent years, as an observation method of an endoscope, a white light observation method using white illumination light (white light) and a narrow band light observation method using illumination light (hereinafter referred to as “special light”) including two narrow band light beams included in blue and green wavelength bands are widely known. Among these methods, the narrow band light observation method can obtain an image that highlights capillaries, the microscopic pattern of a mucosa, and the like that are present in the mucosal surface layer of a living body.
As an endoscope that performs such a narrow band light observation method, there has been known a technique with which information on a special light observation image captured with special light is combined with one normal light observation image captured with white light, whereby capillaries, the microscopic pattern of a mucosa, and the like that are present in the mucosal surface layer of a living body is observed using one observation image (see Japanese Patent No. 5501210). With this technique, frequency processing using a filter such as a high-pass filter or a band-pass filter is performed on the special light observation image, whereby capillaries are extracted from the special light observation image and an extracted result is combined with the normal light observation image to generate an observation image.